Repeating polyphase circuit interrupter



May 20, 1958 A. VAN RYAN El AL 2,835,

REPEATING POLYPHASE CIRCUIT INTERRUPTER Filed July 12, 1954 4 Sheets-Sheet l MN Q E 9 .5 m w.

{NvEN'roRs ANTHONY VAN Rvam -KAZUO HENRY DATE ATTORNEY May 20, 1958 A. VAN RYAN ET AL 2,835,763

REPEATING POLYFHA'SE CIRCUIT INTERRUPTER Filed July 12. 1954 l 4 Sheets-Sheet 2 lNVENTORS ANTHOHY VAN RYAN KAzuo HENRY DATE BVWM KW- ATTORNEY May 20, 1958 A. VAN RYAN El AL 2,835,763

REPEATING POLYPHASE CIRCUIT INTERRUPTER Filed July 12, 1954 4 Sheets-Sheet 3 \NVENTORS ANTHONY VAN RYAH WKW- ATTORNEY KALUO HENRY DATE y 1958 A. VAN RYAN ET AL 2,835,763

REPEATING POLYPHASE CIRCUIT INTERRUPTER Filed July 12; 1954 4 Sheets-Sheet 4 mvam'oas ANTHONY VAN RYAN KAzuo- HENRY DATE.

CZW

ATTORNEY REPEATBJG PULYPHASE CERLCUIT INTERRUITER Anthony ran Ryan and Kaauo Henry Date, South Milwaukee, Wis, assignors to McGraw-Edison Company, a corporation of Delaware Application l'uly 12, 1954, Serial No. 442,572

Claims. (Cl. tl--98) differences from, that disclosed in our prior application,-

Serial No. 379,046, now Patent No. 2,804,521, filed September 8, 1953, for Circuit interrupter, and assigned to the same assignee as the present application. This invention has some of the same general objects as those developed in the prior application noted hereinabove and also differs materially in certain respects therefrom. In the prior invention as in the present invention the circuit interrupter is power reset, the power being stored in power springs, and is tripped upon overload through any one of a plurality of series coils. As in the prior application, the circuit interrupter forming the subject matter of the present application has among other objects that of providing for one or more quick operations followed, if desired, by one or more slow interrupting operations if the overload continues, and which therefore has two time current characteristics and may be coordinated with fuses in branch lines following the circuit interrupter. It has further objects such as providing for lockout after a predetermined number of operations occurring in rapid succession, and also which is so arranged that if these operations occur at widely spaced intervals automatic resetting of a single cumulative means for the full number of subsequent operations is obtained.

Further objects are to provide a polyphase circuit interrupter in which although the overload may occur in a single phase, it nevertheless opens all of the phases simultaneously.

In the prior application noted above the tripping action due to any series coil causes detachment of the remaining tripping means. This has been found highly desirable under certain conditions but under other and rarer conditions it has been found undersirable. For example, if one of the tripping means is functioning and is delayed and a heavy overload occurs on another phase such other phase is ineffective in the prior application to cause tripping of the circuit interrupter.

This invention is designed to overcome the above noted defects and objects of this invention are to provide a circuit interrupter in which the tripping means that is responding to the heaviest overload always takes precedence over any other tripping means that may be functioning and thus causes opening of the circuit interrupter after an interval of time proportional to the heaviest overload.

' In greater detail, further objects are to provide tripping means for each phase so that each tripping means acts independently of all other tripping means and has its own independent time delay means so that it can function to cause tripping of the interrupter at any time even though some other tripping means is functioning and is being delayed.

The above object may be further stated in a more general way, viz., to provide a circuit interrupter in which though one tripping means is functioning and is being delayed by its time delay means that, nevertheless, if a Patent ice much heavier overload should occur in another phase that such heavier overload will immediately become effective to open the circuit interrupters although such last mentioned tripping means is also being delayed in its action.

A further specific object of this invention is to provide a time delay means which has an inverse relation to the magnitude of the overload and which is so constructed that if the overload increases the inverse relation is increased by the automatic adjustment of the time delay means. Although the prior invention had the immediate- 1y above stated object the present invention has such object also and provides a different construction from that of the prior invention as the quick relief valve for the return stroke of the time delay means is independent of the automatically self-adjusting valve that determines the inverse relation hereinabove noted.

An embodiment of the invention is shown in the accompanying drawings in which:

Figure 1 is a side view of the circuit interrupter removed from the casing andwith the cover removed, such view showing the parts in switch closed position.

Figure 2 is a view showing the main latch for latching the toggle link mechanism which normally connects the main power bar with the resetting plunger.

Figure 3 is a view similar to Figure 2 showingthe toggle link broken, or in other words showing the main latch tripped and in the position it occupies only instantaneously before the magnet plunger has risen.

Figure 4 is a fragmentary view partly in section showing the counting means or cumulative means.

Figure 5 is a fragmentary plan view showing the lockout and time delay controlling bar and showing the transfer means and the second time delay controlling bar with other parts of the apparatus omitted.

Figure 6 is a fragmentary side view of the structure shown in Figure 5, such view being drawn to an enlarged scale.

Figure 7 is an end view of one of the time delay devices such view being partly in section.

Figure 8 is a side view partly in section of the structure shown in Figure 7. I

Figure 9 is an enlarged sectional view of the piston structure of the time delay means.

Referring to the drawings, particularly Figure 1, it will be seen that the polyphase circuit interrupter comprises a plurality of switch assemblies indicated generally by the reference character 1, each being operated by means of a switch rod 2, operatively connected to rock arms 3 which in turn are connected to a power bar 4 hiased by the power springs 5 to switch open position. The switch is latched in closed posit-ion by means of latch mechanism indicated generally at 6 in Figures 2 and 3 which serve to latch the toggle link mechanism 7, 8 in extended position as shown in Figure 2. The latch is tripped by means of a pin 9 which strikes the finger 1t) of the latch upon the occurrence of an overload. The

pin 9 is carried by a trip bar 11, see Figures 1 and 2. This allows the toggle link to collapse and allows all of the switches to simultaneously open through the medium of the power bar 4 and power spring means 5.

The circuit interrupter forming the subject matter of this invention is designed to have one or more quick opening strokes and one or more delayed opening strokes as is set forth in detail in the copending application hereinabove. Each switch assembly is connected in series with a series overload coil 12 which is operatively connected by means of the arm 13 with a trip bar operating arm 14. These arms are rigidly connected to a rockshaft 15 in each instance. The series coils are provided with plungers or armatures which are connected by means of links 16 with the arms 13, the links and plungers being biased upwardly by means of the springs 17.

Each of the arms 14 is adapted to shift the trip bar 11 to the right and thus cause the pin 9, see Figures 1 and 2, to engage the trip finger It) and trip the circuit interrupter and allow all of the switches to open.

Time delay means indicated generally by the reference character 18 is provided for each switch assembly. Each time delay means includes a member 19 located eX- ternally of the casingZl) or body portion of the time delay means and is adapted to be engaged by a hook-like lever 21 pivotally mounted on the arm 13, see Figure l. The hook-like members are initially held out of engagement with the pins 22 carried by the members 39 by means of a time delay controlling bar 23. The bar 23 is provided with pins 24 which engage the hook-like members 21 and normally hold them against their spring bias and out of engagement with the pins 22 of the members The bar 23 is guided in any suitable manner as by means of slots 24' which receive pins 25 supported on the housing 20, see Figure 1. The amount of delay is controlled by the adjustment of the over-hanging bracket 26 which may be locked in adjusted position by means of the thumbnut 18'.

The control bar 23 for the t'nne delay means is urged towards the right as viewed in Figure 1 by the spring biased arms or hook-like members 21 but is prevented from moving to the right by means of an arm 27 rigid with a rockshaft 28, see Figure 5. The rockshaft constitutes a transfer means and is spring biased in a counterclockwise direction by means of a spring 29 and is rotated in a clockwise rotary manner by means of an arm 34? which is loose on the rockshaft and engages a pin 31 carried by an arm 32 rigidly mounted on the rockshaft or transfer shaft 28. The arm 30 is rotated in a step-by-step manner by the cumulative piston or counting piston of the cumulative means indicated generally by the reference character 35. This cumulative means consists of a pump member 36 which pumps into a cylinder 37 of the cumulative piston 34 for each operation of the circuit interrupter and advances the cumulative bar 33 in a step-by-step manner. After a predetermined number of operations the hook-like members 21 are allowed to engage the pins 22 of the time delay arms 19 and to thus retard the motion of the arms 13 which are operated by the series overload electromagnets 12, see Figure 1.

Any suitable means may be provided for adjusting the number of operations of the circuit interrupter before the time delay effect will be produced. For example, a pin 38, see Figures 5 and 6 may be carried by a plate 39 adjustably mounted on the time delay control bar 23. The pin 38 engages the arm 27, see Figures 5 and 6, and normally holds the time delay controlling bar 23 against motion to the right as viewed in Figures 1, 5 and 6. The plate 39 is provided with a pin 4G which may enter any one of a plurality of holes 41 formed in the bar 23 and maybe clamped in place by means of a thumbnut It is to be noted that the cumulative means is mounted on the opposite side of the chassis from that shown in Figure l and consequently Figure 4 is reversed with reference to Figures 1 and 6. it is also to be understood that the circuit interrupter is mounted within a casing, not shown, which is oil-filled to a predetermined level, as set forth in our prior application noted hereinabove.

it is also to be understood that the circuit interrupter is automatically reset by means of the resetting electromagnet 43, see Figure l which is described in detail in the above noted copending application.

The time delay means 18 consists of the body portion 20, see Figures 7 and 8, which is provided with a cylinder portion 44- within which a piston 45 slides. The piston is spring biased upwardly by means of a spring 46, see Fi ure 3, and provided. with an orifice thercthrough provided with a restricted portion 47 controlled by Valve means 43. This valve means is urged downwardly by means of a loading spring 49 and carries an O-shaped sealing ring 50. Also, it is to be noted, that the valve means 48 is provided with a tapered shank 51 which projects through the constricted opening 47 and thus controls the effective area of the opening as the valve means is urged upwardly by liquid pressure below the piston 45, it being understood that the body portion is filled with oil or other suitable liquid. The cylinder 44 communicates with the upper chamber 52 but such communication is controlled by means of a valve 53 which is opened on the upstroke of the piston 45 to allow a quick return stroke but which is closed on the downstroke of the piston. The valve 53 is provided with a small opening 54 so that fluid can pass such valve in a limited or restricted amount.

The member 19 bears against a pin 55 guided by the extended collar 56 supported from the body portion and urged upwardly by the spring 46 acting through the piston 45 and through the perforated top 57 forming the portion of the piston and rigid therewith as shown clearly in Figure 8.

- The operation of the time delay means is as follows:

When an overload occurs and the time delay means is eifective to delay the downstrolre of one or more of the series electromagnets the member 19 is rocked downwardly thus displacing the piston 45. The downward motion of the piston is delayed due to the restricted flow of fluid from beneath the piston. However, the valve means 48 opens in proportion to the force ofthe downstroke or in other words, in proportion to the pressure of the liquid below the piston. Obviously, the delay period is inversely proportional to the force of the overload. However, this inverse relation is automatically enhanced by the opening of the valve means 48 so that the inverse relation is automatically changed and the time delay automatically shortened for increasing value of overloads.

A particular feature of this invention distinguishing it from our prior application noted hereinabove is that each time delay means acts independently of every other time delay means and consequently if an overload of moderate intensity occurs in one phase and an overload of greater intensity occurs in another phase simultaneously or while the delay exists with reference to the first phase, the series electromagnet responding to the greater of the two overloads will take charge of the time delay actually imposed on the circuit interrupter prior to opening. The result of this is that, as distinguished from the prior invention, a time delay means is provided for each phase and the time delay means operating for that phase most heavily overloaded will control the amount of delay imposed on the circuit interrupter. This insures the opening of the circuit interrupter for the heaviest overload in the shortest time delay period irrespective of the operation of any other time delay means.

It will be seen that a novel form of circuit interrupter has been provided by this invention which is so constructed that a time delay means is provided for each phase and that each time delay means has a delay period which varies inversely with the intensity of the overload and in which this inverse relation is automatically changed so that the delay period is automatical y shortened to a greater extent than a straight inverse relation for increasing values of overload.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

We claim:

1. A polyphase circuit interrupter comprising a plurality of switch means, power means biasing said switch means towards open position for causing simultaneous opening of all of said switch means, latch means restraining said switch means from opening, a plurality of overload responsive means for releasing said latch means upon the occurrence of an overload in any phase, delay means for each overload responsive means, each overload responsive means being free 01 the remaining overload responsive means whereby upon simultaneous operation of two or more overload responsive means the overload responsive means responding to the heaviest overload will cause opening of the circuit interrupter.

2. A polyphase circuit interrupter comprising a plurality of switch means arranged with a switch means for each phase, power means biasing said switch means towards open position for causing simultaneous opening of all of said switch means, latch means holding said switch means closed, a plurality of releasing electromagnetic means for releasing said latch means upon the occurrence of overload in any phase with a releasing means operatively connected in each phase, and a delay means for each releasing means with each delay means operatively independent of the remaining delay means, each releasing means being permanently effective to release said latch means independently of the delayed action of any other electromagnetic releasing means.

3. A polyphase circuit interrupter comprising a plurality of switch means arranged with a switch means for each phase, power means biasing said switch means towards open position for causing simultaneous opening of all of said switch means, latch means holding said switch means closed, a plurality of releasing electromagnetic means for releasing said latch means upon the occurrence of overload in any phase with a releasing means operatively connected in each phase in series relation to the corresponding switch means, and a delay means for each releasing means with each delay means operatively independent of the remaining delay means, each releasing means being permanently effective to release said latch means independently of the delayed action of any other electromagnetic releasing means.

4. A polyphase circuit interrupter comprising a plurality of switch means arranged with a switch means for each phase, a power bar operatively connected to each switch means for simultaneous operation of said switch means, biasing means biasing said power bar towards switch-open position, latch means restraining said power bar, a plurality of latch-releasing overload electromag- 6 netic means for independently releasing said power bar with a releasing means operatively connected in each phase, and a continuous trip bar for releasing said latch means, said trip bar being movable to releasing position by independent or joint action of said latch-releasing means.

5. A polyphase circuit interrupter comprising a plurality of switch means arranged with a switch means for each phase, a power bar operatively connected to each switch means for simultaneous operation of said switch means for temporary overload in any phase, biasing means biasing said power bar towards switch open position, latch means restraining said power bar, a plurality of latch-releasing overload electromagnetic means for independently releasing said power bar with a releasing means operatively connected in each phase, power means for resetting said power bar after each operation up to lockout, a continuous trip bar for releasing said latch means, said trip bar being movable to releasing position by independent or joint action of said latch-releasing means, normally inactive time delay means for each releasing means, and counting means controlling said time delay means and operable in a step-by-step manner for successive operations of said circuit interrupter for rendering said time delay means effective to delay said releasing means.

References Cited in the file of this patent UNITED STATES PATENTS 

